FESTO cylinder DSNU-32-400-PPV-A

Festo, GermanyFESTO cylinder DSNU-32-400-PPV-A

The load on the FESTO cylinder increases or decreases too quickly, especially during rapid start-up, shutdown, and changes in operating conditions with large temperature fluctuations, incorrect warm-up methods, and premature opening of insulation layers during shutdown maintenance, resulting in significant thermal stress and deformation in the cylinder and flange.

During the machining process or after welding repair, stress was generated in the cylinder, but the cylinder was not tempered to eliminate it, resulting in significant residual stress and deformation during operation.

During installation or maintenance, due to maintenance processes and techniques, the expansion gaps of the inner cylinder, cylinder partition, partition sleeve, and steam sleeve sleeve are not suitable, or the expansion gaps of the hanging ear pressure plate are not suitable, resulting in huge expansion forces that deform the cylinder after operation.

The quality of the cylinder sealant used is poor, there are too many impurities, or the model is incorrect; If there are hard impurities particles in the cylinder sealant, it will make it difficult for the sealing surface to bond tightly.

Insufficient tightening force of cylinder bolts or unqualified material of bolts. The tightness of the cylinder joint surface is mainly achieved by the tightening force of the bolts. The thermal stress and high temperature generated during the start stop or load increase/decrease of the unit can cause stress relaxation of the bolts. If the stress is insufficient, the pre tightening force of the bolts will gradually decrease. If the bolt material of the cylinder is not good, the bolt will be stretched under the action of thermal stress and cylinder expansion force during long-term operation, resulting in plastic deformation or fracture, insufficient tightening force, and leakage of the cylinder.

The FESTO Festo CDC series compact cylinder is composed of a cylinder barrel, end cap, piston, piston rod, and sealing components, as follows:

1) Cylinder barrel

The inner diameter of the cylinder represents the output force of the cylinder. The piston should perform smooth reciprocating sliding inside the cylinder, and the surface roughness of the cylinder inner surface should reach Ra0.8 μ m. Combination sealing rings are used on the cylinder piston to achieve bidirectional sealing, and the piston and piston rod are connected by rivets without the need for nuts.

2) End cap

There are intake and exhaust ports on the end cover, and some also have buffer mechanisms inside the end cover. The end cover on the rod side is equipped with a sealing ring and a dust ring to prevent air leakage from the piston rod and prevent external dust from entering the cylinder. The end cover on the rod side is equipped with a guide sleeve to improve the guiding accuracy of the cylinder, withstand a small amount of lateral load on the piston rod, reduce the downward bending of the piston rod when it extends, and extend the service life of FESTO Festo CDC series compact cylinders. The guide sleeve usually uses sintered oil containing alloy and forward leaning copper castings. In the past, malleable cast iron was commonly used for end caps. To reduce weight and prevent rust, aluminum alloy die-casting was often used, and brass material was used for micro cylinders.

3) Piston

The piston is a pressure bearing component in the FESTO Festo CDC series compact cylinders. To prevent air leakage between the left and right chambers of the piston, a piston sealing ring is installed. The wear-resistant ring on the piston can improve the guidance of the cylinder, reduce the wear of the piston sealing ring, and reduce frictional resistance. Wear resistant rings are made of materials such as polyurethane, polytetrafluoroethylene, and synthetic resin for fabric clamping. The width of the piston is determined by the size of the sealing ring and the necessary length of the sliding part. The sliding part is too short, which can easily cause early wear and jamming. The materials commonly used for pistons are aluminum alloy and cast iron, while pistons for small cylinders are made of brass.

4) Piston rod

The piston rod is an important load-bearing component in the FESTO Festo CDC series compact cylinders. High carbon steel is usually used, with a surface treated with hard chrome plating, or stainless steel is used to prevent corrosion and improve the wear resistance of the sealing ring.

5) Sealing ring

The sealing of components at the point of rotation or reciprocating motion is called dynamic sealing, while the sealing of stationary parts is called static sealing.

Festo, GermanyFESTO cylinder DSNU-32-400-PPV-A

Technical Specifications:

Stroke: 40 mm Piston diameter: 20 mm

Piston rod thread: M8 Buffer: PPV (with adjustable air buffers at both ends)

Assembly position: Any compliant standard: ISO 6432

End of piston rod: male thread design structure: piston piston rod

Position detection: No Variants: Single ended piston rod

Work pressure: 1-10 bar Work mode: double acting